A three-year research project is proposed to study intensively both the process and outcome of therapy for a group of 70 families with a child between six and 12 years old referred for treatment of child problems. A preliminary purpose is to test the assumption that changes in family management skills are related to changes in child criterion behaviors (both prosocial and antisocial). The role of client cooperation as a mediator in determining changes in measures of family-management skills (baseline to termination and follow-up) will be examined. After a four-stage screening process to determine eligibility, an intensive, multilevel, multimodal assessment for criterion measures (including microsocial observations in the home, parent daily reports of symptom occurrence, parent interpersonal functioning, mood, crises, social isolation, marital adjustment, child school adjustment, and child social skills [including peer adjustment]) will be conducted. Next, families will be randomly assigned using an alternation technique to experimental treatment (OSLC, N = 50) or treatment in the community agency comparison group (Looking Glass, N = 20). Multilevel-multimode treatment process measures will be collected for each group, including client measures collected at each session (social isolation, crises, mood, positive parenting, and client's perception of client-therapist relationship); therapist measures collected at each session (client cooperation, involvement, and likeability ratings, a log of contact, and client completion of homework assignments), and therapy observation measures collected during the beginning, middle, and late stages of treatment (including microsocial observations of client and therapist behavior and coder ratings). Families in both the experimental and comparison groups will be reassessed at treatment termination an six-month follow-up using the complete battery that was administered at baseline. This intensive assessment effort allows for careful examination of the relationship among several constructs thought to be central to statistically signficant and clinically meaningful change in families of antisocial youth. It is hypothesized that (1) there will be significnt changes in the criterion measures of child behavior from pre- to post-treatment for the experimental group but not for the comparison group, (2) changes in parental family-management practices will account for significant variances in changes in the criterion measures, and (3) changes in scores on pre/post family-management variables are mediated by parental cooperation within and between sessions and by therapist behavior within sessions.